1. Field of the Invention
The present invention generally relates to liquid filters and/or strainers. More specifically, the present invention relates to a liquid filter with a process input connection positioned at a bottom of the filter housing.
2. Description of Related Art
Liquid filters are used in a wide range of processes to remove contaminants from liquids.
Prior liquid filters, for example as shown in FIG. 1 and further disclosed in U.S. Pat. No. 4,701,259, “Fluid Filter with Filter Retainer”, by Nils Rosaen, issued Oct. 20, 1987, are configured with a filter element suspended within a cylindrical housing supported by a filter basket. In a filtering mode, process liquid flows through a sidewall inlet port into an upper area of the housing. Process liquid passing through the filter element and filter basket exits the housing through an outlet port at the bottom of the housing. The filter housing is accessed, for example to exchange the filter element, via a top cover. To provide the housing with sufficient pressure capacity, the planar top cover is formed from a metal plate material of increased thickness.
When the process is interrupted for filter maintenance, unless additional valving and process piping is applied to drain the filter housing, when the top cover is removed to access the filter, the filter housing may remain full of liquid, requiring the operator to reach into the process liquid to grasp the submerged filter element.
Should process flow through the filter momentarily reverse, for example due to hydraulic shocks during process interruptions and/or interconnection changes, the filter basket and/or filter may lift from its supporting filter basket and/or sidewall shoulder enabling process fluid to bypass the filter element. Prior liquid filter housings have applied additional structures, such as spider arrangements and/or retaining legs extending inward from the top cover to retain the filter element and/or filter basket in place. These additional structures provide surfaces on which process liquid contaminant buildup and/or fouling may occur.
Competition within the liquid filter industry has focused attention upon minimization of materials and manufacturing costs. Also, ease of installation/service, and requirements for interconnecting piping are significant factors for commercial success.
Therefore, it is an object of the present invention to provide an apparatus that overcomes deficiencies in the prior art.